If you don't think one mouse that your currently feeding is enough you can feed 2 in one feeding. As soon as he gets one down offer another. You could do that until you can get pups. My 213g killerbee female eats large mice, going to try to switch to rat pups soon. The pet store I bought her from was feeding small mice and they were way to small. But the large mice called arctic mice from pet smart weigh in around 20g give or take 1 gram or 2.
Edit: sorry I thought you were still currently feeding small mice but I just went through again and you said prior to this. But still if you ever need to your allowed to feed more then one rodent if your snake won't switch to rats or if there is not other option.
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